In the field of measuring the amount of hydrocarbons, which cause photochemical smog, it has been known to use a total hydrocarbon content analysis method such as the FID (flame-ionization detecting method). However, it is desired to employ continuous measurement of the concentrations of other hydrocarbons than methane as a hydrocarbon measuring method for monitoring air-pollution, since it has been revealed that methane does not take part in formation of photochemical smog to the extent that other hydrocarbons do.
The present invention relates to a method for the separation of methane from hydrocarbons other than methane which can be employed in hydrocarbon-detecting device and the like.
It is also well-known that there is a remarkable difference in oxidation temperature between the group methane, ethane and propane and the other hydrocarbons other than the above three types of hydrocarbons. Consequently, it is possible to employ this difference in oxidation-reaction temperature to separate methane, ethane and propane from these other hydrocarbons.
However, it is very difficult to separate methane from ethane and propane by this method because of their similarity in chemical activity.
It is strongly desired to develop a method for separating methane from ethane and propane in order to obtain greater precision in a hydrocarbon measuring device for monitoring atmospheric air pollution, since propane gas has been commonly used as a domestic and automobile fuel.